#include "fio.h"
#include "blktrace_api.h"
+#define TRACE_FIFO_SIZE (sizeof(struct blk_io_trace) * 1000)
+
+/*
+ * fifo refill frontend, to avoid reading data in trace sized bites
+ */
+static int refill_fifo(struct thread_data *td, struct fifo *fifo, int fd)
+{
+ char buf[TRACE_FIFO_SIZE];
+ unsigned int total, left;
+ void *ptr;
+ int ret;
+
+ total = 0;
+ ptr = buf;
+ while (total < TRACE_FIFO_SIZE) {
+ left = TRACE_FIFO_SIZE - total;
+
+ ret = read(fd, ptr, left);
+ if (ret < 0) {
+ td_verror(td, errno, "read blktrace file");
+ return -1;
+ } else if (!ret)
+ break;
+
+ fifo_put(fifo, ptr, ret);
+ ptr += ret;
+ total += ret;
+ }
+
+ return 0;
+}
+
+/*
+ * Retrieve 'len' bytes from the fifo, refilling if necessary.
+ */
+static int trace_fifo_get(struct thread_data *td, struct fifo *fifo, int fd,
+ void *buf, unsigned int len)
+{
+ int ret;
+
+ if (fifo_len(fifo) >= len)
+ return fifo_get(fifo, buf, len);
+
+ ret = refill_fifo(td, fifo, fd);
+ if (ret < 0)
+ return ret;
+
+ if (fifo_len(fifo) < len)
+ return 0;
+
+ return fifo_get(fifo, buf, len);
+}
+
/*
* Just discard the pdu by seeking past it.
*/
* due to internal workings of the block layer.
*/
static void handle_trace(struct thread_data *td, struct blk_io_trace *t,
- unsigned long long ttime, unsigned long *ios)
+ unsigned long long ttime, unsigned long *ios,
+ unsigned int *bs)
{
int rw;
return;
rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0;
+
+ if (t->bytes > bs[rw])
+ bs[rw] = t->bytes;
+
ios[rw]++;
+ td->o.size += t->bytes;
store_ipo(td, t->sector, t->bytes, rw, ttime);
}
*/
int load_blktrace(struct thread_data *td, const char *filename)
{
- unsigned long long ttime;
+ unsigned long long ttime, delay;
struct blk_io_trace t;
unsigned long ios[2];
+ unsigned int cpu;
+ unsigned int rw_bs[2];
+ struct fifo *fifo;
int fd;
fd = open(filename, O_RDONLY);
return 1;
}
- ios[0] = ios[1] = 0;
+ fifo = fifo_alloc(TRACE_FIFO_SIZE);
+
+ td->o.size = 0;
+
+ cpu = 0;
ttime = 0;
+ ios[0] = ios[1] = 0;
+ rw_bs[0] = rw_bs[1] = 0;
do {
- /*
- * Once this is working fully, I'll add a layer between
- * here and read to cache trace data. Then we can avoid
- * doing itsy bitsy reads, but instead pull in a larger
- * chunk of data at the time.
- */
- int ret = read(fd, &t, sizeof(t));
+ int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t));
- if (ret < 0) {
- td_verror(td, errno, "read blktrace file");
+ if (ret < 0)
goto err;
- } else if (!ret) {
+ else if (!ret)
+ break;
+ else if (ret < (int) sizeof(t)) {
+ log_err("fio: short fifo get\n");
break;
- } else if (ret != sizeof(t)) {
- log_err("fio: short read on blktrace file\n");
- goto err;
}
if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) {
td_verror(td, ret, "blktrace lseek");
goto err;
}
- if (!ttime)
+ if (!ttime) {
ttime = t.time;
- handle_trace(td, &t, t.time - ttime, ios);
+ cpu = t.cpu;
+ }
+ delay = 0;
+ if (cpu == t.cpu)
+ delay = t.time - ttime;
+ handle_trace(td, &t, delay, ios, rw_bs);
ttime = t.time;
+ cpu = t.cpu;
} while (1);
close(fd);
if (!ios[DDIR_READ] && !ios[DDIR_WRITE]) {
log_err("fio: found no ios in blktrace data\n");
return 1;
- } else if (ios[DDIR_READ] && !ios[DDIR_READ])
+ } else if (ios[DDIR_READ] && !ios[DDIR_READ]) {
td->o.td_ddir = TD_DDIR_READ;
- else if (!ios[DDIR_READ] && ios[DDIR_WRITE])
+ td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
+ } else if (!ios[DDIR_READ] && ios[DDIR_WRITE]) {
td->o.td_ddir = TD_DDIR_WRITE;
- else
+ td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
+ } else {
td->o.td_ddir = TD_DDIR_RW;
+ td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
+ td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
+ }
/*
* We need to do direct/raw ios to the device, to avoid getting